Marta and Ana are great friends, despite the fact that they have practically incompatible temperaments. Marta is independent, liberal and single. Ana is married and her life revolves around her husband, Santi. But a cloud hangs over Santi, for the last five years he has been having an affair with Marta and fears Ana will find out. What Santi doesn't know is that he is the one being deceived. It was Ana who convinced Marta to start a relationship with her husband. Everything appears to be perfect until their conscience begins to get the best of them.